SNAS506I January   2011  – December 2014 LMP91000

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 I2C Interface
    7. 6.7 Timing Requirements
    8. 6.8 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Potentiostat Circuitry
        1. 7.3.1.1 Transimpedance Amplifier
        2. 7.3.1.2 Control Amplifier
        3. 7.3.1.3 Variable Bias
        4. 7.3.1.4 Internal Zero
        5. 7.3.1.5 Temperature Sensor
        6. 7.3.1.6 Gas Sensor Interface
          1. 7.3.1.6.1 3-Lead Amperometric Cell in Potentiostat Configuration
          2. 7.3.1.6.2 2-Lead Galvanic Cell In Ground Referred Configuration
          3. 7.3.1.6.3 2-lead Galvanic Cell in Potentiostat Configuration
        7. 7.3.1.7 Timeout Feature
    4. 7.4 Device Functional Modes
    5. 7.5 Programming
      1. 7.5.1 I2C Interface
      2. 7.5.2 Write and Read Operation
    6. 7.6 Registers Maps
      1. 7.6.1 STATUS -- Status Register (Address 0x00)
      2. 7.6.2 LOCK -- Protection Register (Address 0x01)
      3. 7.6.3 TIACN -- TIA Control Register (Address 0x10)
      4. 7.6.4 REFCN -- Reference Control Register (Address 0x11)
      5. 7.6.5 MODECN -- Mode Control Register (Address 0x12)
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Connection of More Than One LMP91000 to the I2C BUS
      2. 8.1.2 Smart Gas Sensor Analog Front-End
      3. 8.1.3 Smart Gas Sensor AFES on I2C BUS
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Sensor Test Procedure
      3. 8.2.3 Application Curve
  9. 9 Power Supply Recommendations
    1. 9.1 Power Consumption
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Trademarks
    2. 11.2 Electrostatic Discharge Caution
    3. 11.3 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

9 Power Supply Recommendations

9.1 Power Consumption

The LMP91000 is intended for use in portable devices, so the power consumption is as low as possible in order to ensure a long battery life. The total power consumption for the LMP91000 is below 10 µA at 3.3 v average over time, (this excludes any current drawn from any pin). A typical usage of the LMP91000 is in a portable gas detector and its power consumption is summarized in Table 3. This has the following assumptions:

  • Power On only happens a few times over life, so its power consumption can be ignored.
  • Deep Sleep mode is not used.
  • The system is used about 8 hours a day, and 16 hours a day it is in Standby mode.
  • Temperature Measurement is done about once per minute.

This results in an average power consumption of approximately 7.95 µA. This can potentially be further reduced, by using the Standby mode between gas measurements. It may even be possible, depending on the sensor used, to go into deep sleep for some time between measurements, further reducing the average power consumption.

Table 3. Power Consumption Scenario

Deep Sleep StandBy 3-Lead Amperometric Cell Temperature Measurement
TIA OFF		 Temperature Measurement TIA ON Total
Current consumption
(µA)
typical value		 0.6 6.5 10 11.4 14.9
Time ON
(%)		 0 60 39 0 1
Average
(µA)		 0 3.9 3.9 0 0.15 7.95
Notes
A1 OFF ON ON ON ON
TIA OFF OFF ON OFF ON
TEMP SENSOR OFF OFF OFF ON ON
I2C interface ON ON ON ON ON